Re: Re: Move softcursor out of fbdev to fbcon

[Jon Smirl <jonsmirl@gmail.com>]

On 7/27/05, Antonino A. Daplas <adaplas@gmail.com> wrote:
> Jon Smirl wrote:
> > On 7/27/05, Antonino A. Daplas <adaplas@gmail.com> wrote:
> >> The changelog says it all. This is a modification of Jon's patch, but
> >> I have moved softcursor.c to the console directory.  Also I removed
> >> the "select FB_SOFTCURSOR" from video/Kconfig and made the compilation
> >> of softcursor unconditional, if framebuffer console is enabled.
> >>
> >> I don't think the fb_cursor hook is usable by other programs, so we
> >> should just restrict this hook for fbcon use only.  For userspace cursor
> >> support, we need a new one.  But instead of one function, I believe
> >> it's better to provide several.  Ie, something like below:
> >>
> >> fbcursor_show()
> >> fbcursor_move()
> >> fbcursor_loadimage()
> >> fbcursor_loadpalette()
> >> fbcursor_start()
> >> fbcursor_stop()
> >
> > What does start/stop do?
> 
> Wrong choice of words, this is just an example.  But start() should tell
> the driver that the cursor is going to be used, and perhaps do some locking (so
> another app does not try to grab the device).  It can also return the
> capabilities of the cursor: maximum dimensions, color depth of image,
> caps such as alpha, transparency, etc.  stop() will release the cursor.

In the sysfs model I'd do something like this. Most attributes are read/write.
cursor_visible -- 0/1 hide/show
cursor_location -- x,y
cursor_image -- image bitmap
cursor_palette -- pallete data
cursor_capabilities -- read only

An owner could have a lot of problems, what if the owning apps dies?
There is no open file handle in the sysfs model. I would just assume
that ownership is handled in the upper layers.

Sysfs is still an experiment to see if it really can handle everything
the IOCTLs do.

-- 
Jon Smirl
jonsmirl@gmail.com


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